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We set up an original apparatus to measure the grain grain friction stress inside a granular medium composed of sodo‐silicate‐glass beads surrounded by a water vapor atmosphere.We analyze here the influence of the physico chemistry of water on our glass beads and its consequences on our shear experiment. We found two scales in the analysis of the shear stress signal. On the microscopic scale of one bead, the experimental results show a dependence on the size of beads, on the shear rate and on humidity for the resulting stick slip signal. On the macroscopic scale of the whole assembly of beads, the behavior of the total amplitude of the shear stress depends on the size of the beads and is humidity dependent only for relative humidity larger than 80%. For high degrees of humidity, on the microscopic scale, water lubricates the surface of the beads leading to a decrease in the microscopic resistance to shear while on the macroscopic scale the resistance to shear is increased: the assembly of very humid grains behaves as a rheothickening fluid.

The purpose of this monograph is to present the first English translation of a unique French colonial report on women living under colonial rule in West Africa.

The issue begins with a discussion of the contribution this report makes to the history of social development policy in Africa, and how it serves the on‐going critique of colonisation. This is followed by the English translation of the original report held in the National Archives of Senegal. The translation is accompanied by explanatory notes, translator’s comments, a glossary of African and technical terms, and a bibliography.

The discussion highlights contemporary social development policies and practices which featured in identical or similar forms in French colonial social policy.

As the report demonstrates, access to basic education and improving maternal/infant health care have dominated the social development agenda for women in sub‐Saharan Africa for over a century, and will continue to do so in the foreseeable future in the Millennium Development Goals which define the international community’s agenda for social development to 2015. The parallels between colonial and post‐colonial social policies in Africa raise questions about the philosophical and cultural foundations of contemporary social development policy in Africa and the direction policy is following in the 21st century.

Though the discussion adopts a consciously postcolonial perspective, the report that follows presents a consciously colonial view of the “Other”. Given the parallels identified here between contemporary and colonial policy‐making, this can only add to the value of the document in exploring the values that underpin contemporary social development practice.

Reinforcing steel bars in concrete structures exposed to tropical marine atmospheres experience very high corrosion rates due to several environmental factors. The aim of this research was mainly to elucidate if zinc‐coated rebars may delay the onset of corrosion and/or extend the service life of infrastructure in the tropics, as the approach is promising in other atmospheres.

Hot‐dip zinc‐coated and plain steel rebars were embedded in concrete cylinders made with local aggregates and having four different water‐to‐cement ratios. Samples were exposed during 24 months at the marine breeze in a coastal site in the Gulf of Mexico. The corrosion behaviour of zinc‐coated and uncoated rebars was monitored by means of corrosion potential and linear polarization resistance techniques. Also, carbonation penetration and the chloride ingress were measured and correlated with the corrosion behaviour.

Only under the worst case conditions (concrete with 0.7 w/c ratio) did galvanized steel experience corrosion initiation. It was shown to resist higher chloride levels than uncoated steel and extended the onset of corrosion.

The effectiveness of the zinc‐coated bar for corrosion control is controversial and its use mainly is supported by accelerated tests or application in cold or subtropical environments. This research showed the corrosion behaviour in an extremely corrosive tropical zone.

THE ordinary work study practitioner will naturally ask what difference a European Work Study Federation will make to him. If it is to have his whole‐hearted support he will need to be satisfied that it will bring him advantages he would not obtain otherwise. It is too early to give precise answers to such questions. There are, however, some reasonable deductions that can be made.

Millions of properties have suspended timber ground floors globally, with around ten million in the UK alone. However, it is unknown what the floor void conditions are, nor the effect of insulating such floors. Upgrading floors changes the void conditions, which might increase or decrease moisture build-up and mould and fungal growth. The purpose of this paper is to provide a review of the current global evidence and present the results of in situ monitoring of 15 UK floor voids.

An extensive literature review on the moisture behaviour in both uninsulated and insulated suspended timber crawl spaces is supplemented with primary data of a monitoring campaign during different periods between 2012 and 2015. Air temperature and relative humidity sensors were placed in different floor void locations. Where possible, crawl spaces were visually inspected.

Comparison of void conditions to mould growth thresholds highlights that a large number of monitored floor voids might exceed the critical ranges for mould growth, leading to potential occupant health impacts if mould spores transfer into living spaces above. A direct comparison could not be made between insulated and uninsulated floors in the sample due to non-random sampling and because the insulated floors included historically damp floors. The study also highlighted that long-term monitoring over all seasons and high-resolution monitoring and inspection are required; conditions in one location are not representative of conditions in other locations.

This study presents the largest UK sample of monitored floors, evaluated using a review of current evidence and comparison with literature thresholds.

High volume airless spray coating unit. Developed as a multi‐gun unit, the portabe ARO 650–819 unit provides maximum spraying performance for the high volume application of most materials including enamels, metallic paints, high build epoxies and other anti‐corrosive coatings.

This paper aims to provide a critical review of water generation from atmospheric air by using desiccant materials. Over the past few years, there has been very high stress on water scarcity, especially in Asian and African countries. Because of this insecurity, many countries are focusing on their research in the field of water technologies. Water generation from atmospheric air by using desiccant materials is one of the techniques among the air-to-water generators (AWGs).

A structured and systematic literature review has been presented to observe and understand the past trend/patterns in the field of water generation from atmospheric air by using desiccant materials. To understand the water generation technologies based on desiccant materials, the research papers from the years 1987 to 2022 have been studied and included.

The properties of the different and most probable desiccant materials in the field of AWGs have been discussed. A detailed review of testing reports of collected water samples has also been presented in tabular form. Finally, the economic analysis has been done and future prospects have been discussed. It is also found that the capacity of solid desiccant materials to adsorb the water is less as compared to liquid desiccant materials. But, the adsorption capacity can be improved by using composite desiccant materials.

The uniqueness of this manuscript lies in the compiling and examination of the existed published research papers, including variables such as author, year and geographical location, experimental/simulative, types of desiccant material, type of setup, desiccant material type and quantity and type of concentrator. This manuscript provides critique to the empirical and conceptual research in AWG technologies and also stimulates researchers to explore the topic very carefully.

The construction, use and demolition of buildings carry enormous environmental burdens. As one step to reduce a building’s environmental impact, green building design guidelines and certification programs, such as Leadership in Energy and Environmental Design, Cradle to Cradle and the Whole Building Design Guide, promote the specification of alternative, non-traditional building materials. Alternative materials carry a variety of potential benefits: reducing the amount of energy and other resources needed to create building materials; creating healthier indoor and outdoor environments; diverting or reducing waste from landfills; reducing the use of scarce, critical or economically volatile materials; and spurring innovation in the building industry. However, a lack of clarity surrounds alternative materials and creates a barrier to their usage. The purpose of this paper is to review definitions of alternative materials in various design guidelines in order to provide context to their specification and usage.

Through a survey of green building programs and guidelines, existing literature on alternative materials, and life-cycle assessment using multiple inventory databases, this study tackles the following questions: what constitutes an alternative building material; what are the current barriers to their specification; how are they specified in the most common design guidelines; and do alternative building materials present a “greener” alternative?

These results show that while often alternative materials do in fact show promise for reducing environmental impacts of the built environment, by how much can be a challenging question to quantify and depends on a variety of factors. While many green building guides and certification systems provide recommendations for use of alternative materials, the sheer diversity and uncertainty of these systems coupled with the complexity in understanding their impacts still present a significant barrier to their specification. Much work remains in a variety of disciplines to tackle these barriers. A clear emphasis should be on better understanding their environmental impacts, particularly with respect to the context within the built environment that their specification will provide energy, resource and emission savings. Other key areas of significant work include reducing costs, removing regulatory and code barriers, and educating designers, consumers, and end-users.

Alternative materials are defined and specified in a diversity of contexts leaving the design and construction communities hesitant to promote their use; other work has found this to be a key barrier to their widespread usage. By compiling definitions, barriers and design guidelines instructions while also exploring analytically the benefits of specific cases, this work provides a foundation for better understanding where new, more sustainable materials can be successfully specified.

The need to use cleaning methods other than traditional CFC‐113 solvent for hi‐rel electronics imposes more rigid cleanliness testing. In the past, this was mainly limited to ionic contamination control, but this is probably insufficient by itself when using other methods. This paper discusses the various methods for which instrumentation is available, from the practical standpoint. This should satisfy all the requirements of both procurement agencies and manufacturers. Particular emphasis is placed on the fact that most existing standards are out‐of‐date and should be urgently revised. It is suggested that the standards be based on statistically valid test results rather than the simpler, but risky, go/no‐go methods. These probability limit levels should be modulated according to the use to which the circuitry will be put and the technology used in its manufacture. Above all, emphasis is placed on testing methods that are more scientifically based with less empirical guesswork.

Fibre content can influence the intensity of odour that develops within clothing fabrics. However, little is known about how effective laundering is at removing malodours in clothing which differ by fibre type. The purpose of this paper is to investigate whether a selected cotton fabric differed in odour intensity following multiple wear and wash cycles compared to a polyester fabric.

Eight (male and female) participants wore bisymmetrical cotton/polyester t-shirts during 20 exercise sessions over a ten-week trial period. Odour was evaluated via a sensory panel, bacterial populations were counted and selected odorous volatile organic compounds were measured with comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry detection. Analysis occurred both before and after the final (20th) wash cycle.

Findings showed that laundering was effective in reducing overall odour intensity (p0.001) and bacterial populations (p0.001) in both cotton and polyester fabrics. Odour was most intense on polyester fabrics following wear, not just before, but also after washing (p0.001); although, no differences in bacterial counts were found between fibre types (p>0.05). Chemical analysis found C4-C8 chained carboxylic acids on both types of unwashed fabrics, although they were more prevalent on polyester.

The findings suggest that the build-up of odour in polyester fabrics may be cumulative as important odorants such as the carboxylic acids were not as effectively removed from polyester compared to cotton.